The point, then, is that when a lengthy ḥadīth is transmitted—say, through two entirely separate lines of transmission with no prior collusion—it cannot plausibly be a mistake, just as it cannot plausibly be a fabrication. Error does not normally encompass an entire, multi-faceted narrative; it touches only parts of it. Thus, if one transmitter relates a long, detailed story and another conveys it exactly as the first did, without having agreed in advance, the possibility of error in the whole of it is precluded, just as the possibility of deliberate invention, absent collusion, is precluded.

Accordingly, when a slip does occur in such a case, it will concern only some incidental detail of the account—like the ḥadīth describing the Prophet’s purchase of a camel from Jābir. Anyone who studies its various chains knows with certainty that the report itself is authentic, even though the narrators differed over the exact price. Al-Bukhārī clarified this in his Ṣaḥīḥ. Indeed, most of what is contained in the collections of al-Bukhārī and Muslim belongs to this category, and one can be sure that the Prophet ﷺ actually said it. First, the bulk of their material has this very profile; second, the scholars have received it with acceptance and affirmation, and the Muslim community cannot unanimously agree upon an error. Were a ḥadīth false in reality, yet the umma accepted and believed it, they would be unanimously affirming something that is, in fact, a lie—an impossible consensus on error. True, in the absence of consensus we do allow for the possibility that a report contains a mistake or fabrication, but this is analogous to allowing—before learning of any consensus—that a ruling inferred from an explicit text or a probable analogy might be wrong in reality. Once they concur on a ruling, however, we are certain that it is correct both inwardly and outwardly.

For this reason, the great majority of scholars from every school hold that a khabar al-wāḥid (a solitary report) which the umma has accepted—whether by affirming its truth or by acting upon it—conveys certain knowledge. This is the position set down in the works on legal theory by the disciples of Abū Ḥanīfa, Mālik, al-Shāfiʿī and Aḥmad. Only a small group of later scholars, following a faction among the theologians, rejected it. Yet many, indeed most, theologians side with the jurists, the ḥadīth specialists and the early generations on this point, and it is the view of the majority